Sugino

Sugino is a white tengu and the "god" of Sugino Village. As such, he is often called Sugino-sama. Unlike a black tengu, who is born a tengu, a white tengu was originally a powerful, overly-proud human priest or monk who changed into a tengu. Before Kantarou had tried, Sugino had attempted to break Haruka's seal, but failed. Sugino has a great amount of dislike for the human race, having been a human himself. Sugino is married to Muu-chan, a small, green youkai. Upon being asked how they would reproduce, Sugino states that their relationship is platonic. Prior to meeting Muu-chan, Sugino was a cruel character who earned the nickname of 'violent tengu'.

His cruelty caused him to be lonely and hate his immortality. Source: Wikipedia.